Banded cat shark red underneath

This is a discussion on Banded cat shark red underneath within the Saltwater Fish Diseases forums, part of the Saltwater Fish and Coral Reef Tanks category; -->
Hi all
I purchased a small banded shark yesterday and this evening it died,
Up on looking at it the belly had red patchies ...

I purchased a small banded shark yesterday and this evening it died,
Up on looking at it the belly had red patchies on it! And not sure why! Was just about to feed tank!
Water change done weekly round 20%

Yeah took over hour to acclimatise in to tank. Getting refund not an issue, just wounded why died ! Might change sand for all fine and again!
I had not fed him! But have read that if feed something to big they can bend like a banna
To try and digest there food, could that have been an issue?